


Prove It

by elrhiarhodan



Category: Captain America (Movies), Iron Man (Movies), Marvel Cinematic Universe
Genre: M/M, Masturbation, Pi, UST, dares, little Steve
Language: English
Status: Completed
Published: 2015-05-09
Updated: 2015-05-09
Packaged: 2018-03-29 18:18:19
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,148
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3906058
Author URL: https://archiveofourown.org/users/elrhiarhodan/pseuds/elrhiarhodan
Summary: <blockquote class="userstuff">
              <p>Steve eggs Tony on, and Tony is not a man who backs down from a challenge. Even if it involves him jerking off.  And reciting Pi.  Sequel to <a href="http://archiveofourown.org/works/3897217">Up For a Challenge</a>.</p>
            </blockquote>





	Prove It

“Prove it.”

Tony blinked, not quite sure that the words he heard were actually the words that came out of Steve’s mouth.

“What? You too old? You’ve forgotten the first two hundred and fifteen digits of Pi? You can’t get it up?”

Tony checked the whiskey bottle, sniffing it carefully. Thor wasn’t a prankster, but he just might have tipped a few drops of his special Asgardian brew into it. There was probably nothing else that would affect Captain America quite so badly.

“I’m not drunk, Tony.”

“You sure? Maybe I am, because I think I just heard you ask me to pull out my dick and jerk off while reciting Pi to the two hundred and fifteenth digit.”

Steve shrugged. “I’ve got nothing better to do.”

He was Tony Stark, Genius Billionaire Playboy Philanthropist, and occasional asshole. He was never at a loss for words. He had a quip or a comeback for every moment. Except this. 

“What’s the matter, afraid?”

Tony managed to croak out, “Afraid of what?”

“Coming up short?” Steve was leaning back against the couch - manspreading - taking up all the space and maybe all of the oxygen, too. His thighs were parted and Tony couldn’t help but notice the rather prominent bulge between them. Was Captain America turned on or was that his normal resting state. 

Tony licked his lips to keep from drooling, and from somewhere, he found something that resembled a comeback. “I am prodigy in _every_ respect. Not even a dose of your Super Serum could give you what I’ve got.”

“Oh? I’m not so sure about that. I might have been short and slight before the serum, but not everywhere.” Steve glanced down at his crotch. “Didn’t need much enhancement there. My pants were loose for a reason - it was hard to find trousers that fit but didn’t strangle the guy. And the guy got plenty of action.”

Tony remembered his father talking about Steve Rogers, a man pure of soul, incorruptible, above base human appetites like lust. And yet here he was, sitting on his couch, talking about his dick. It was not only disconcerting, it was arousing.

“I think you have Howard’s files from the original experiments, right?”

Tony nodded, and when he realized he was massaging his dick, he pulled his hand away and quickly crossed his legs.

“JARVIS?”

“Yes, Captain Rogers?”

“Can you pull up my pre-serum health records?”

“Yes, certainly.”

Tony squeezed his eyes shut and wondered, _Why, oh why did I give Steve command access to JARVIS?_

A stack of files appeared as a holographic display, “Which images are you looking for?”

“Photographs from my physical exams.”

Tony was familiar with some of the images JARVIS presented: young Steve Rogers, scrawny, but trying to make himself appear bigger, shoulders back, chin high, staring into the camera. JARVIS scrolled the sequence, Steve in civilian dress, then in his first - too-big - army uniform, then in his shorts and t-shirt, measured at regular intervals during basic training. The rest of the photos were new to Tony - the ones where the t-shirt disappeared as someone wrapped a tape measure around his biceps and his chest. There were photos of his abdomen and then a few of Steve's - now clearly naked - buttocks. 

Tony hoped he didn’t groan out load. Steve - pre-serum - had the same perfect bubble butt that he did now.

And finally, the last set of pictures were full frontal. Steve Rogers, circa 1939, five-foot-five and hung like a fucking horse.

“How did you climb the stairs with that?” The words erupted out of his mouth.

“Believe me, after a long day in Basic, it wasn’t easy.”

Tony just shook his head.

“Anyway, we weren’t really talking about the size of my penis. We were talking about your ability to wank and recite Pi. I don’t believe you can really do it.”

“Let me get this straight. You - Captain America - want to see me, Tony Stark - jerk off while reciting Pi to the two-hundred and fifteenth digit.”

“If you can.” Steve reached into this pocket, pulled out his wallet and dropped a fifty onto the table. “Bet you can’t.”

Tony wasn’t going to let this bet go unanswered. He took out his wallet and dropped his own fifty on the table. “Just so we’re clear - you want to watch me stroke my cock and recite Pi?”

“And you can’t come until you reach the two-hundred and fifteenth digit.”

“You know, that’s not much of a challenge.”

“Stop stalling, Stark. Whip it out.”

Tony promised himself that he’d find out if someone had replaced Captain America with an evil android, but right now, he had wood in his pants and a dare to beat.. He stood up, better to give a good show, undid his belt, unzipped his fly and pulled Not-So-Little Tony out. It would be better if he had some of his SI-formulated artesianal lube, but saliva would have to do. It sufficed for the original challenge all those years ago and it would work now. He spat into his palm and staring into Steve’s eyes, got started. 

“3-point-1-4-1-5-9-2-6-5-3-5-8-9-7-9-3-2-3-8-4-6-2-6-4-3-3-8-3-2-7-9-5-0 …” The first thirty digits tripped off his tongue, his cock felt delicious - it always did - and pleasure rolled through him. The next thirty or so were just as pleasurable, “2-8-8-4-1-9-7-1-6-9-3-9-9-3-7-5-1-0-5-8-2-0-9-7-4-9-4-4-5-9-2-3-0-7-8.”

He closed his eyes, getting lost in the numbers. Pure math wasn’t his thing, but he always appreciated the exquisite complexity of Pi. 

“1-6-4-0-6-2-8-6-2-0-8-9-9-8-6-2-8-0-3-4-8-2-5-3-4-2-1-1-7-0-6-7-9-8-2-1-4” Tony reached a hundred digits and it felt like he could go on forever, stroking and counting and calculating. His balls were tingling, but nothing felt imminent. “8-0-8-6-5-1-3-2-8-2-3-0-6-6-4-7-0-9-3-8-4-4-6-0-9-5-5-0-5-8-2-2-3-1-7…”

It was embarrassing - how quickly he shot his load back then. _Two-hundred-fifteen digits, that’s nothing._. “2-5-3-5-9-4-0-8-1-2-8-4-8-1-1-1-7-4-5-0-2-8-4-1-0-2-7-0-1-9-3-8-5-2-1-1-0-5-5-5-9-6-4-4-6-2-2-9-4-8…”

With twenty-five digits left to go, Tony made the mistake of opening his eyes. Steve was still manspread on his couch, but he had taken his own dick out and was jerking off, too. His hand was slowly stroking that monster, loosely wrapped around it, as if he was in no hurry. But Tony could see the tension in Steve’s arm, the veins beginning to pop.

Their eyes met again and Steve licked his lips. “You’re twenty-five digits short, Stark - you lose track or something?”

Tony slowed his hand down and widened his stance. He’s balls were about to blow, but he wasn’t going to lose this bet. Not with his honor at stake. “9-5-4-9-3-0-3-8-1-9-6-4-4-2-8-8-1-0-9-7-5-6-6-5-9-3-3-4-” He shouted the last number as come exploded out of him, streaks of white decorating everything in the blast radius, including Captain America, who was coming, too. And coming. And coming.

As Tony sank back onto the couch, a dozen highly inappropriate thoughts wandered through his mind. Almost all of them involved Captain America’s dick.

“I have to say, Tony - I am impressed. You beat your old record. You got to the two-hundred and eighteenth digit. Maybe you’ll get to two-hundred-twenty next time.”

__

FIN


End file.
